#include<iostream>
#include<vector>
#include<cmath>
using namespace std;

vector<int> primeFactors(int n)
{
    vector<int> result;
    while(n%2==0)
    {
        result.push_back(2);
        n = n / 2;
    }
    for(int i=3;i<sqrt(n);i+=2)
    {
        while(n%i==0)
        {
            result.push_back(i);
            n = n / i;
        }
    }
    if(n > 2)
    {
        result.push_back(n);
    }
    return result;
}
int main()
{
    vector<int> result;
    result = primeFactors(90);
    for(int i=0;i<result.size()-1;i++)
    {
        cout<<result[i]<<'*';
    }
    cout<<result[result.size()-1];
    return 0;
}